Method of and means for forming a selvage on fabric woven on a shuttleless loom



March 28, 1967 KoKK|N|$ 3,311,138

METHOD OF AND MEANS FOR FORMING A SELVAGE ON FABRIC WOVEN ON A SHUTTLELESS LOOM Filed Sept. 9, 1964 4 Sheets-Sheet 1 INVENTOR. NIKOLAUS KOKKINIS ATTORNEY March 28, 1967 N. KOKKINIS 3,311,138

METHOD OF AND MEANS FOR FORMING A SELVAGE ON FABRIC WOVEN ON A SHUTTLELESS LOOM 4 Sheets-Sheet 2 Filed Sept. 9, 1964 INVENTOR. NIKOLAUS K OKKINIS ATTORNEY March 28, 1967 N. KOKKINIS 3,311,138

METHOD OF AND MEANS FOR FORMING A SELVAGE 0N FABRIC WOVEN ON A SHUTTLELESS LOOM Filed Sept. 9, 1964 4 Sheets-Sheet 3 INVENTOR.

Y NIKOLAUS KOKKINIS ATTORNEY March 28, 1967 N. KOKKINIS 3,311,133

METHOD OF AND MEANS FOR FORMING A SELVAGE I ON FABRIC WOVEN ON A SHUTTLELESS LOOM Filed Sept. 9, 1964 4 Sheets-Sheet 4 Fig. 7

INVENTOR NIKOLAUS KOKKINIS ATTORNEY United States The invention relates to the production of fabric by a shuttleless loom wherein.the Weft threads are inserted alternatingly from the sides of the fabric, for example by means of gripper systems. The weft threads are pulled from stationary spools and cut at predetermined lengths. Looms operating in this manner have the disadvantage that no normal selvages are formed as are formed when weaving on shuttle looms, and weft thread ends project more or less from the edge of the fabric. Since no real selvage is formed the fabric has an unattractive appearance and its fitness for further operations is reduced.

It has been tried to remove or prevent projecting weft thread ends in various manners and to form a selvage. It is diflicult to cut off the weft thread ends because they are easily bent and avoid the cutting tool. The weft thread ends have been made fast by twisted warp threads and cut thereafter. This method, however, was only partly satisfactory and it was not possible to obtain a clean selvage. In other weaving methods the projecting weft thread ends are tucked in by means of special selvageforming devices. Thereby the unattractive, projecting thread ends are avoided but the selvage is thicker and more bulky than the rest of the fabric. In another method the weft threads are so cut that they end within the fabric. This, however, cannot be done with the exactness required to avoid short projection of the weft thread ends, or to prevent damage of the edge of the fabric itself when the weft threads are too short. None of the conventional methods for forming a selvage on a fabric Woven on shuttleless looms completely avoids the technical deficiencies of artificial selvages and undesired irregular edges of the fabric.

It is an object of the present invention to avoid the aforedescribed disadvantages and to provide a method for forming a selvage on a fabric woven on a shuttleless loom whereby the weft threads are alternatingly inserted on opposite sides and to produce a selvage which is as normal as possible. This object is obtained according to the invention by performing the following steps:

(a) Provision of a number of additional warp threads at either side and outside of the width of the fabric proper;

(b) Forming a shed by the additional warp threads in a special rhythm which is different from the shed-forming rhythm of the warp threads of the fabric proper;

(c) Cutting the weft threads bound in the additional warp threads for removing the ribbon formed by the addi tional warp threads and the weft thread ends bound thereby.

The additional warp threads may be of an inferior quality compared with that of the warp threads of the fabric proper.

The novel features which are considered characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, and additional objects and advantages thereof will best be understood from the following description of embodiments thereof when read in connection with the accompanying drawing wherein:

FIG. 1 is a schematic plan View of a fabric wherein the weft threads are alternatingly inserted twice from the right side and twice from the left side.

atent O FIG. 2 is a schematic end View of the fabric shown in FIG. 1, looking in the direction of arrow A, and diagrammatically illustrates the rhythm of the shed formation of the additional warp threads when weaving a fabric as shown in FIG. 1.

FIG. 3 is a schematic plan view of a fabric wherein the weft threads are alternatingly inserted once from the right side and once from the left side.

FIG. 4 is a schematic end view of the fabric shown in FIG. 3, looking in the direction of arrow A, and diagrammatically shows the rhythm of the shed formation of the additional warp threads when weaving a fabric according to FIG. 3.

FIG. 5 is a plan view of a portion of a loom showing more particularly a finished fabric, the insertion of weft threads and the formation of the selvages according to the invention.

FIG. 6 is a side view of a preferred cutting device for use in the method according to the invention.

FIG. 7 is a diagrammatic part-sectional illustration of the drive means for the heddles forming the sheds of the additional wrap threads at the sides of the warp threads producing the fabric proper.

FIG. 8 is a diagrammatic side view of the fabric woven on a loom having heddle drive means as shown in FIG. 7.

In the example shown in FIGS. 1 and 2 a fabric is produced generally in the conventional manner by inserting weft thread alternatingly twice from the right side and twice from the left side. The letter K designates normal warp threads, i.e. the warp threads forming the fabric proper. Outside of the desired width of the fabric which is indicated by dash-dot lines, additional warp threads Z are provided. The rhythm of the shed formation according to the new method is illustrated on two additional warp threads z1 and 22.

The additional Warp threads on either side of the fabric proper form sheds in a special rhythm which is different from the rhythm of the shed formation by the warp threads of the fabric proper.

Production of the fabric is not described in detail because it is conventional. Weft threads 2b and 2a are consecutively inserted, for example, first from the left side whereby the bend formed by the weft threads 2b and 2a is properly bound whereafter weft threads 1b and 1a are inserted from the right side whereby the bend formed by these two weft threads is bound at the right side of the fabric. According to the invention, the length of the free ends of the weft threads 1a, 1b, and 2a, 2b is greater than the length which corresponds to the actual width of the fabric to be woven and the free ends of the Weft threads are bound in the additional warp threads. For this purpose the additional warp threads at one side of the fabric are made to form a shed when a weft thread is inserted from the opposite side of the fabric. In this case the projecting weft thread ends are bound in the additional warp threads Z, as in a regular fabric. Since, when inserting weft thread from one side there is no shed formation, the addition warp threads Z remain unaffected during this phase of operation and the weft thread is bound by the first or outermost normal warp thread K in the conventional manner. FIG. 1 shows that at the right side the weft thread 1a, 1b forms a bend or weft loop around the first or outermost normal warp thread K and re-v mains unaffected by the additional warp threads, for ex-v ample zl and 2:2, whereas the free ends 111 and 1b of this weft thread are bound at the left side of the fabric in the additional warp threads Z provided thereat. The situation for the weft thread 2a, 2b is analogous but reversed as to sides. The bend or weft loop is formed around the outermost left normal warp thread K and the weft thread ends 2a and 2b are bound at the right side by the addit1ona1 warp thre-ads Z1 and Z2. Therefore, it is seen that the shed of the additional warp threads on one side is open while the shed of the adidtional warp threads on the other side is closed for receiving and binding only the weft thread ends in the additional warp threads on the one side. Likewise, the shed of the additional warp threads on the one side isclosed while the shed of the additional warp threads on the other side is open for receiving and binding only the weft thread ends into the additional warp threads on the other side.

FIG. 2 illustrates the rhythm of the shed formation by the additional warp threads 21 and Z2. A shed is formed consecutively twice in order to bind the free weft thread ends, for example 2a and 2b, whereupon the shed remains open twice in order to make possible formation of a bend and normal binding of the weft thread, for example 1, on the first, i.e. outermost, normal warp thread. The rhythm of the shed formation by the additional warp threads on the opposite side of the fabric is equally timed but at a predetermined phase displacement. It is essential that shed formation takes place only when the weft thread is inserted from the opposite side.

As has been said before, the dash-dot lines indicates the width of the fabric to be woven and therefore also indicate the cutting line along which later-on the weft thread ends which are bound in the additional warp threads Z are cut whereby a clean and exact cut is obtained with no thread end projecting. Cutting off the projecting weft thread ends means a small loss which, however, is compensated by obtaining a selvage after cutting of the weft thread ends and removal of the additional warp threads, wherein every second weft thread is bound and the free weft thread ends are cut close to the outermost warp thread of the fabric proper. Such an edge or selvage cannot be distinguished from a normally bound selvage as is produced on a shuttle loom. The edge obtained according to the invention is not bulky, is attractive and has no imperfections.

In FIG. 3 the warp threads are arranged as in FIG. 1. Weft insertion, however, does not occur twice in immediate succession from one side and thereafter twice from the other side, but one weft thread is inserted from one side whereafter a weft thread is inserted from the opposite side. Projecting weft thread ends are bound and thereafter cut in the previously described manner by forming sheds by the additional warp threads in a special rhythm. This rhythm is shown in FIG. 4 whereby the projecting weft thread ends of every other weft thread, for example. 2a and 2b are bound between the warp threads 21 and Z2. The intermediate weft threads, for example 1a and 1b, are not affected by the additional warp threads at the right side of the fabric and form a bend in the conventional manner and are bound by the outermost warp thread K.

FIG. 5 shows the entire method. The letter K desi nates the normal warp threads and the letter Z designates the additional warp threads. W1 and W2 designate heddles for forming the sheds for the fabric to be woven. At the left side are heddles W3 and W4 and on the right side are heddles W5 and W6 which pairwisely cooperate and are moved in a rhythm which is different from the rhythm in which the heddles W1 and W2 are moved. The pair of heddles W3, W4 is active when the pair of heddles W5, W6 is at rest, and conversely. Means for actuating the heddles are diagrammatically shown in FIG. 7. The heddles W1 and W2 form the sheds of the main warp threads and are actuated in the conventional manner. The heddles W3 and W4 which form the sheds of the additional warp threads for forming a selvage at the left side are actuated by cams E3 and E4, respectively. The heddles W5 and W6 which form the sheds of the addtional warp threads at the right side are actuated by cams E5 and E6, respectively. All cams are mounted on a common shaft, in the conventional manner. The direction of rotation of the cams is indicated by arrows.

FIG. 8 shows a diagrammatic side view of a selvage woven with heddle drive means as shown in FIG. 7.

G1 and G2 designate two gripper systems which move in the direction of the arrows shown in FIG. 5 for pulling a weft thread F from a stationary spool Sp at the right side of the loom and inserting the weft thread into the shed. FIG. 5 shows that the weft thread inserted from the right side is bound on the outermost right warp thread K. The heddles W5 and W6 at the right side do not form a shed whereas the pair of heddles W3, W4 at the left side form a shed for binding the projecting weft thread ends. There is a stationary weft thread spool, not shown, also on the left side for supplying the weft threads inserted from the left side. The finished fabric G moves in the conventional manner through temples B. Adjacent each temple and where the fabric leaves the temples a cutting device M is placed at either side of the fabric for cuttin the bound weft thread ends and removing the additional warp threads Z.

FIG. 6 shows a suitable cutting device M for cutting off the marginal portion of the fabric or ribbon formed by the additional warp threads and projecting weft thread ends. It is of advantage to use a disclike knife whose edge S is undulated axially of the knife. At the side of the marginal portion to be cut off the cutting device is provided with an ami'ular groove U of U-shaped crosssectional configuration which groove or recess is placed between the cutting knife and an annular bulge R. Due to the U-shaped groove or recess the cut-off marginal strip of the fabric with the additional warp threads is slightly twisted by the resulting tension so that the weft thread ends remain well fixed between the warp threads and are not pulled out by the cutting operation. The device shown in FIG. 6 affords use of only a few additional warp threads Z and assures a good hold of the weft thread ends. If a knife without the annular U-shaped groove is used, considerably more additional warp threads must be provided in order to sufficiently securely bind the weft threads.

The annular knife may be so installed that its position is automatically adjusted according to the correct width of the marginal strip if the fabric proper temporarily moves sideways. For this purpose the knife shown in FIG. 6 is arranged axially movably on its shaft N. A slight pressure of a spring 0 presses the knife towards the fabric proper. If, during regular weaving, the edge of the fabric laterally moves to one side or to the opposite side the edge S of the cutting knife follows the path of the outermost regular warp thread K and leans on this warp thread. Therefore, cutting is effected always at the once adjusted width of the marginal strip at the correct location between the outermost regular warp thread K and the innermost additional warp thread Z. The edge of the cutting knife itself effects the correct guidance. The shaft N is preferably mounted on the same support part P of the loom as is the temple B and the entire assembly B, M, P is laterally displaceable to accommodate the desired fabric width.

As has been explained, the method according to the invention produces a selvage which cannot be distin guished from a conventionally bound selvage. The selvage produced according to the invention is not bulky and has no projecting thread ends. The method can easily be implemented because only the cutting device for cutting the weft threads at the innermost of only a few additional warp threads need be provided. The additional warp threads can easily be rigged. Separate actuation of the heddles for the additional warp thread can be provided without great difiiculty.

I claim:

1. A method of forming a selvage on fabric woven on a shuttleless loom having gripper systems, comprising the steps of:

providing a plurality of main warp threads;

pulling weft threads from relatively stationary spools,

and cutting the weft threads at predetermined lengths;

inserting weft threads from one side, of said main warp threads, into sheds formed by said main Warp threads to form weft loops on said one side and weft thread ends on said other side;

inserting weft threads from the other side, of said main warp threads, into sheds formed by said main warp threads to form weft loops on said other side and Weft thread ends on said one side; providing a first plurality of additional warp threads on said one side of said main warp threads completely outside of the weft loops on said one side;

providing a second plurality of additional warp threads on said other side of said main warp threads completely outside of the weft loops on said other side;

closingt-he shed of said first plurality of additional warp threads simultaneously opening the shed of said second plurality of additional warp threads, and simultaneously receiving and binding only the weft thread ends projecting from said other side into the shed formed by said second plurality of additional warp threads;

closing the shed of said second plurality of additional warp threads, simultaneously opening the shed of said first plurality of additional warp threads and simultaneously receiving and binding only the weft thread ends projecting from said one side into the shed formed 'by said first plurality of additional warp threads;

cutting the weft thread ends between said main Warp threads and each of said pluralities of additional warp threads;

and removing the additional Warp threads with the weft thread ends bound by the additional warp threads.

2. A method as defined in claim 1 wherein the fabric is distended by temples and the weft thread ends are cut adjacent the side of the temples where the fabric leaves the temples.

3. A method as defined in claim 1 wherein shedding of the additional warp threads at said one side of said main warp threads is effected only when a weft thread is inserted from the opposite side of the warp.

4. A method according to claim 3 wherein the shed opening and shed closing of the additional warp threads at one side of the warp is like the shed opening and shed closing of the additional warp threads at the opposite side of the warp, but the phase of the shedding at one side of the warp is shifted relative to the phase of the shedding at the opposite side of the warp.

5. In a shuttleless loom for weaving having gripper means for pulling weft threads from relatively stationary spools and cuting the weft threads into predetermined lengths;

said gripper means for inserting weft threads from one side, of the fabric to be woven, into sheds formed by the warp threads of the fabric to be woven to form weft loops on said one side and weft thread ends on said other side;

said gripper means inserting weft threads from the other side, of the fabric to be woven, into sheds fromed by the warp threads of the fabric to be woven to form weft loops on said other side and weft thread ends on said one side;

means providing a first plurality of additional warp threads on said one side completely outside of the weft loops on said one side;

means providing a second plurality of additional warp threads on said other side completely outside of 7 the weft loops on said other side; first means for shedding said first plurality of additional 6 warp threads separately from the warp threads of the fabric to be woven;

second means for shedding said second plurality of additional warp threads separately from the warp threads of the fabric to be woven; said second means closing the shed of said second plurality of additional warp thread substantially simultaneously with said first means opening the shed of said first plurality of additional Warp threads for receiving and binding, in the additional warp threads, only the weft thread ends projecting from said one side and inserted from said other side of the fabric to be woven; said first means closing the shed of said first plurality of additional Warp threads substantially simultaneously with said second means opening the shed of said second plurality of additional warp threads for receiving and binding, in the additional warp threads, only the weft thread ends projecting from said other side and inserted from said one side of the fabric to be woven;

cutting means placed between the outermost warp threads of the fabric to be woven and the innermost warp threads of each of said pl-uralities of additional warp threads for cutting the weft thread ends and removing the additional warp threads from the weft thread ends bound by the additional warp threads.

6. In a shuttleless loom as defined in claim 5, wherein each of said cutting means includes a circular rotatable knife having a cutting edge undulated axially of said knife.

7. In a shuttleless loom as defined in claim 6 and wherein each of said cutting means is provided with an annular bulge coaxial of said knife and with an annular groove coaxial of said knife and between said knife and said bulge, the latter being opposite the innermost of the respective additional warp threads and said knife being opposite the outermost of the warp threads of the fabric to be woven at the edge of the fabric opposite the innermost respective additional warp thread which is opposite said bulge.

8. In a shuttleless loom as defined in claim 5 and wherein said cutting means is axially movable.

9. In a shuttleless loom as defined in claim 6 and wherein said cutting means is axially movable and means are provided for urging said knife toward the respective outermost warp thread of the woven fabric.

References Cited by the Examiner UNITED STATES PATENTS 1,384,099 7/1921 Schlegel 139383 1,809,619 6/1931 Brown 139-291 2,389,809 11/ 1945 Moessinger 139-302 2,604,123 7/1952 :Budzyna et al. 139127 2,906,296 9/ 1959 Ancet et al. 139-122 2,924,247 2/ 1960 Flamand 13955 3,108,617 10/1963 Nichols 13955 3,144,882 8/1964 Steiner 139----54 FOREIGN PATENTS 223,951 3 1958 Australia.

625,921 8/ 1961 Canada. 1,309,945 10/ 1962 France. 1,324,932 3/1963 France.

126,556 1/1902 Germany.

277,749 9/ 1927 Great Britain.

424,709 2/ 1935 Great Britain.

979,215 1/ 1965 Great Britain.

0 MERVIN STEIN, Primary Examiner.

DONALD PARKER, Examiner.

J. KEE CHI, Assistant Examiner. 

1. A METHOD OF FORMING A SELVAGE ON FABRIC WOVEN ON A SHUTTLELESS LOOM HAVING GRIPPER SYSTEMS, COMPRISING THE STEPS OF: PROVIDING A PLURALITY OF MAIN WARP THREADS; PULLING WEFT THREADS FROM RELATIVELY STATIONARY SPOOLS, AND CUTTING THE WEFT THREADS AT PREDETERMINED LENGTHS; INSERTING WEFT THREADS FROM ONE SIDE, OF SAID MAIN WARP THREADS, INTO SHEDS FORMED BY SAID MAIN WARP THREADS TO FORM WEFT LOOPS ON SAID ONE SIDE AND WEFT THREAD ENDS ON SAIID OTHER SIDE; INSERTING WEFT THREADS FROM THE OTHER SIDE, OF SAID MAIN WARP THREADS, INTO SHEDS FORMED BY SAID MAIN WARP THREADS TO FORM WEFT LOOPS ON SAID OTHER SIDE AND WEFT THREAD ENDS ON SAID ONE SIDE; PROVIDING A FIRST PLURALITY OF ADDITIONAL WARP THREADS ON SAID ONE SIDE OF SAID MAIN WARP THREADS COMPLETELY OUTSIDE OF THE WEFT LOOPS ON SAID ONE SIDE; PROVIDING A SECOND PLURALITY OF ADDITIONAL WARP THREADS ON SAID OTHER SIDE OF SAID MAIN WARP THREADS COMPLETELY OUTSIDE OF THE WEFT LOOPS ON SAID OTHER SIDE; CLOSING THE SHED OF SAID FIRST PLURALITY OF ADDITIONAL WARP THREADS SIMULTANEOUSLY OPENING THE SHED OF SAID SECOND PLURALITY OF ADDITIONAL WARP THREADS, AND SIMULTANEOUSLY RECEIVING AND BINDING ONLY THE WEFT THREAD ENDS PROJECTING FROM SAID OTHER SIDE INTO THE SHED FORMED BY SAID SECOND PLURALITY OF ADDITIONAL WARP THREADS; CLOSING THE SHED OF SAID SECOND PLURALITY OF ADDITIONAL WARP THREADS, SIMULTANEOUSLY OPENING THE SHED OF SAID FIRST PLURALITY OF ADDITIONAL WARP THREADS AND SIMULTANEOUSLY RECEIVING AND BINDING ONLY THE WEFT THREAD ENDS PROJECTING FROM SAID ONE SIDE INTO THE SHED FORMED BY SAID FIRST PLURALITY OF ADDITIONAL WARP THREADS; CUTTING THE WEFT THREAD ENDS BETWEEN SAID MAIN WARP THREADS AND EACH OF SAID PLURALITIES OF ADDITIONAL WARP THREADS; AND REMOVING THE ADDITIONAL WARP THREADS WITH THE WEFT THREAD ENDS BOUND BY THE ADDITIONAL WARP THREADS. 